35 - Revolving Tool Station, страница 26
ShopSolutions TIPS FROM OUR SHOP ROUTING JIG___ ■ Cutting the recesses for the brass plates on the torpedo level (page 6) is easy. I just used a router and a straight bit. The trick is getting a seamless fit between the wood body and the curved ends of the brass plates. To do this, I used a guide bushing that attaches to the base of the router and a simple jig, see photo at right. jig. The jig consists of two parts: a hardboard template with a curved notch and two sides that support the base of the router. When determining the size of the curved notch, the thing to keep in mind is the bit won't cut right up next to the edge. That's because the guide bushing (not the bit) will ride against the template. As a result, the notch needs to be slightly larger than the desired radius of the recess. To find out how much larger, measure the distance from the cutting edge of the bit to the outer part of the bushing. Then add that TEMPLATE (2" x &" - 1/4"-THICK HARDBOARD) WORKPIECE place, see Fig 1. Note: The depth of cut should equal the thickness of the brass plates, see Fig. la. rout recesses. Now it's just a matter of routing the recesses. After laying out each recess (refer to margin on page 10), position the workpiece in the jig so the mark aligns with the reference shoulder, see Fig. 2a. After tightening the jig (and^fck workpiece) in a vise, you can^^ rout two recesses on the bottom for the wear plates. To rout the recess for the cover plate, you'll need to first rout half the recess, see Fig 2. Then, turn the workpiece end for end and rout the other half. SIDE (2" x 14" - 1'/2"-THICK STOCK) CUT W'-DEEP RABBET y2" WIDE amount to the desired radius of the recess. rabbets. After cutting the curved notch, the template is glued into rabbets cut in the sides of the jig. These rabbets are sized so the sides of the jig fit snug against the level. This way, the workpiece will be pinched between the sides when you tighten the jig in a vise. reference shoulder. Before routing the recess, the next step is to establish a reference shoulder that will help you accurately position the workpiece in the jig. To create this shoulder, rout along the template and sides of the jig ivithout the workpiece in TEMPLATE GUIDE BUSHING ROUT REFERENCE SHOULDER IN TEMPLATE AND SIDE SIDE THICKNESS of BRASS PLATES / / ' SIDE / 7u SECOND: ROUT FIRST HALF OF RECESS SIDE ^ A/ WORKPIECE NOTE: COVER PLATE AREA SHOWN FIRST: position workpiece IN JIG (SEE DETAIL 'a') TOP VIEW shoulder LAYOUT MARK template slide workpiece in until layout mark aligns with shoulder THIRD: TURN WORKPIECE END FOR END TO ROUT OTHER HALF 26 ShopNotes No. 35 |
